1H, 13C and 15N NMR spectra of 15N labeled aromatic hydroxyoxime ligands were reported. 15N chem. shifts exhibit a linear relation with the charge densities. The isotope effect of 15N on 13C NMR was examined Aromatic hydroxyoximes existed as associated mols. in the solution via intra- or intermol. hydrogen bonding.

Key words: NMR SPECTROMETRY, LABELLED COMPOUNDS, IRON COMPLEX, COPPER COMPLEX, OXIME, CHEMICAL SHIFT, HYDROGEN BONDS, COBALT COMPLEX, TRANSITION METAL COMPLEX, NICKEL COMPLEX, STABLE ISOTOPES, CHARGE DENSITY, NITROGEN ISOTOPES, HYDROXYL COMPOUNDS